1. Field of the Invention
The present invention relates to an ink cartridge suitable for an ink jet printer, and more particularly to an ink cartridge having an ink porous member dimensioned to substantially fill the accommodating chamber in an uncompressed manner for efficiently supplying ink to an ink delivery needle of the ink jet printer.
2. The Prior Art
In the conventional ink jet printer, ink is loaded in an ink cartridge for supplying the ink to an ink delivery needle of the ink jet printer due to print paper. Referring to FIG. 1, the ink cartridge generally comprises an ink tank body 1a having an ink tank or a plurality of ink tanks for loading different color ink, wherein the ink tank body 1a is sealed with a cover body 2a thereon for forming a closure. The cover body 2a has an ink charging inlet 20a and an ambient air vent 21a and a sealing film 22a is attached on a top surface of the cover body 2a so as to seal the ambient air vent 21a. The tank body 1a has an ink outlet port 10a formed on a bottom plate 11a thereof and an accommodated chamber 12a defined therein for receiving an ink porous member 3a. Furthermore, in operation, first to remove the sealing film 22a, then to mount the ink cartridge into the ink jet printer, and the ink in fluid communication through the ink outlet port 10a of the ink tank body 1a to an ink delivery needle 5a of the ink jet printer.
However, in the conventional ink cartridge, the ink outlet port 10a is extended and projecting inwardly from an inner surface of the bottom plate 11a of the ink tank body 1a, and the ink porous member 3a originally has a substantially planar bottom surface 30a and its whole dimension is larger than that of the accommodated chamber 12a of the ink tank body 1a, so that the ink porous member 3a with the ink impregnated therein is positioned inside the ink tank body 1a and its substantially planar bottom surface 30a is abutting against the ink outlet port 10a thereby being compressed by the ink outlet port 10a. The pores of the ink porous member 3a are positioned adjacent to the ink outlet port 10a being smaller in size than the pores thereof positioned away from the ink outlet port 10a, which is known as the effect of compression.
Additionally, a stopping member 4a defines a passage 40a formed therein and is arranged in a vent end 13a of the ink outlet port 10a, and a laminated film 14a is sealed on an opening of the vent end 13a of the ink outlet port 10a, so that the laminated film 14a can be pierced by the ink delivery needle 5a that being fitted with the passage 40a of the stopping member 4a. 
Please refer to FIG. 2, to provide an ink cartridge, which comprises a casing 2xe2x80x2a having a bottom wall 3xe2x80x2a which has an inside face 16xe2x80x2a upwardly protruded therefrom, rather than a substantially planar bottom surface, and the inside face 16xe2x80x2a defining an opening 8xe2x80x2a therethrough for being communicated with a print head, and an area of the inside face 16xe2x80x2a of the bottom wall 3xe2x80x2a around the opening 8xe2x80x2a having a plurality of radial grooves 17xe2x80x2a that open to the opening 8xe2x80x2a for the purpose increasing the flow area at the outlet port.
Further, a porous body 12xe2x80x2a is a cuboid body fill in an unfit space of the casing 2xe2x80x2a due to the inside face 16xe2x80x2a of the bottom wall 3xe2x80x2a so as to being slightly compressed by 2% to 6%.
The primary purpose of the present invention is to provide an ink cartridge, which includes an ink tank body with an accommodating chamber defining a dimension being completely same as that of the ink porous member positioned therein in an uncompressed manner, so that the ink porous member is impregnated with ink under low atmospheric pressure thereby to increase the amount of the impregnated ink.
Another purpose of the present invention is to provide an ink cartridge, which includes a stopping member having a sealing film integrally formed therein before the ink cartridge is used to the ink delivery needle without a laminated film sealed on an opening of the ink outlet port.
In accordance with one aspect of the present invention, an ink cartridge includes an ink tank body having a plurality of side walls and a bottom plate for defining an accommodating chamber therein, the bottom plate having an inner surface and an outer surface, a filter disposed on the inner surface thereof so as to form a substantially planar bottom surface of accommodating chamber, and a plurality of through holes formed in the bottom plate below the filter for restricting a flow rate of ink, an ink outlet port protruded outwardly from the outer surface of the bottom plate in aligned relationship with the through holes, a stopping member disposed in the ink outlet port for receiving an ink delivery needle, an ink porous member positioned in the accommodating chamber and having a substantially planar bottom surface relative to the substantially planar bottom surface of the tank body, and the ink porous member dimensioned to substantially fill the accommodating chamber in an uncompressed manner.
It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed. Other advantages and features of the invention will be apparent from the following description, drawings and claims.